Pyrotechnic Compounds

Colors in fireworks are usually generated by pyrotechnic stars—usually just called stars—which produce intense light when ignited. Stars contain five basic types of ingredients.

A fuel which allows the star to burn

An oxidizer—a compound which produces (usually) oxygen to support the combustion of the fuel

Color-producing chemicals

A binder which holds the pellet together.

A chlorine donor which provides chlorine to strengthen the color of the flame. Sometimes the oxidizer can serve this purpose.

Some of the more common color-producing compounds are tabulated here. The color of a compound in a firework will be the same as its color in a flame test (shown at right). Not all compounds that produce a colored flame are appropriate for coloring fireworks, however. Ideal colorants will produce a pure, intense color when present in moderate concentration.

The brightest stars, often called Mag Stars, are fueled by aluminium. Magnesium is rarely used in the fireworks industry due to its lack of ability to form a protective oxide layer. Often an alloy of both metals called magnalium is used.

Many of the chemicals used in the manufacture of fireworks are non-toxic, while many more have some degree of toxicity, can cause skin sensitivity, or exist in dust form and are thereby inhalation hazards. Still others are poisons if directly ingested or inhaled.

Abstract reference of chemicals used in fireworks industry

The following table is an educational guideline for the chemistry of fireworks.

Symbol

Name

Fireworks Usage

Al

Aluminum

Aluminum is used to produce silver and white flames and sparks. It is a common component of sparklers.

Ba

Barium

Barium is used to create green colors in fireworks, and it can also help stabilize other volatile elements.

C

Carbon

Carbon is one of the main components of black powder, which is used as a propellent in fireworks. Carbon provides the fuel for a firework. Common forms include carbon black, sugar, or starch.

Copper produces blue-green colors in fireworks and halides of copper are use to make shades of blue.

Fe

Iron

Iron is used to produce sparks. The heat of the metal determines the color of the sparks.

K

Potassium

Potassium compounds help to oxidize firework mixtures. Potassium nitrate, potassium chlorate, and potassium perchlorate are all important oxidizers. The potassium content can impart a violet-pink color to the sparks.

Li

Lithium

Lithium is a metal that is used to impart a red color to fireworks. Lithium carbonate, in particular, is a common colorant.

Mg

Magnesium

Magnesium burns a very bright white, so it is used to add white sparks or improve the overall brilliance of a firework.

Na

Sodium

Sodium imparts a yellow color to fireworks, however, the color is often so bright that it frequently masks other, less intense colors.

O

Oxygen

Fireworks include oxidizers, which are substances that produce oxygen in order for burning to occur. The oxidizers are usually nitrates, chlorates, or perchlorates. Sometimes the same substance is used to provide oxygen and color.

P

Phosphorus

Phosphorus burns spontaneously in air and is also responsible for some glow in the dark effects. It may be a component of a firework's fuel.